Make a hemisphere/dome from flat segments?
I don't think this topology is the best to make a dome, but here is a solution:


Make sure you've applied the scale of your object.
Shift a bit your mesh from its origin.
Create a curve which follows approximately the curve you want. Check the direction, put its origin at its bottom.
Give your mesh a Curve modifier with the curve as Object.
Create an empty at the same point as the mesh origin.
Give your mesh an Array modifier, give it a Count of 6. Enable Merge, choose the Object Offset mode with the empty as Object.
Rotate the empty 60° on the Z axis. The object should rotate around the Z axis.
Shift the mesh a bit so that its bottom stick to its duplications bottom.
Edit the curve so that the sides of the mesh stick to its duplications.
Edit the object: Select some horizontal edges and scale a bit with the Proportional Editing enabled, so that the vertices of the mesh stick to its duplications.
Once you're glad you can apply the modifiers and remove the doubles (but keep a copy somewhere).
You'll have to make some additional editing to clean it a bit, create some nice edges with bevels, and to avoid artefacts. I've also used a W > Smooth. You may want to work only on 1/6 of the dome and re-use an array to duplicate it again.